This project addresses sleep disorders in pediatrics by developing a miniaturized, light-weight Motionlogger Actigraph for activity monitoring. Previous studies have demonstrated the value of activity monitoring in sleep disorder determination. The sleepless child needs proper diagnosis based on accurate sleep/wake data for guidance in parental education. Pilot studies have demonstrated the feasibility and value of collecting objective data from infants or children independently from parents' reports, which data provides evidence to re-schedule the child's sleep time and educate parents with proof of efficacy of treatment; and a smaller, lightweight unit would be more suitable for use with infants and small children. In Phase I a lightweight, smaller Motionlogger Actigraph with more memory will be fabricated and validated; and actigraphic data will be compared to time lapse video monitoring in a home setting in cooperation with the Sleep Research Center at Bradley Hospital (Brown University). In Phase II software and equipment will be validated with a large patient population in the home setting. Normative data will be collected on children and adolescents.